An isotropic stationary source is emitting waves of frequency n and wind is blowing due north. An observer A is on north of the source while observer B is on south the source. IF both the observers are stationary, then

When the medium moves and the source and observer are stationary:

Stationary Source And Moving Observer

An observer is moving towards the stationary source of sound, then

An observer starts moving with uniform acceleration ‘a’ towards a stationary sound source emitting a whistle of frequency ‘n\ As the observer approaches source, the apparent frequency heard by the observer varies with time as

An observer starts moving with uniform acceleration a towards a stationary sound source emitting a whistle of frequency n . As the observer approaches source, the apparent frequency, head by the observer varies with time as